North Korea building new, larger submarine pens
Nick Hansen, Stanford, California and Jeremy Binnie, London - IHS Jane's Defence Weekly
22 July 2016
North Korea is constructing a fortified structure near the port city of Sinpo that will have what appears to be two covered docks (pens) that could shelter ballistic missile submarines (SSBs).
Located 2.25 km south of the Sinpo shipyard, close to the Mayang-do Naval Base on the country's east coast, the new base may be the largest active military building project in North Korea at the moment.
Commercial satellite imagery shows construction of the base began sometime between August 2009 and November 2012. Much of the harbour seen in 2009 (an area covering some 6,000 m²) had been blocked off by a sea wall and filled in by November 2012. Spoil from the surrounding hills was likely used as filling material.
http://www.janes.com/article/62486/north-korea-building-new-larger-submarine-pens
